Electric furnace.



PATENTED JUNE 13, 1905. F. A. J. FITZ GERALD & P. MON. BENNIE.

ELECTRIC FURNACE.

APPLICATION FILED 1320.3, 1904.

fill 67119725: Kitti -M P Mn 3%, 63 mm (QWWL M tnesses Wu QZW UNITED STATES Patented June 13, 1905.

PATENT OFFICE.

FRANCIS A. J. FITZ GERALD AND PETER MON. BENNIE, OF NIAGARA FALLS, NEIV YORK.

ELECTRIC FURNACE.

SPECIFICATION forming part of Letters Patent No. 792,255, dated June 13, 1905.

Application filed December S, 1904. Serial No. 285,343.

To all 1071/0777, it may concern:

Be it known that we, FnANcIs A. J. Frrz GERALD, a subject of the King of Great Britain, and Farm: MoN. BENNIE, a citizen of the United States, both residing at Niagara Falls, in the county of Niagara and State of New York, have invented certain new and useful Improvements in Electric Furnaces, of which the following is a specification.

This invention is an electric furnace of the resistance type having particular advantages for the economical generation and utilization of heat for the treatment of any desired material, charge, or article.

Referring to the accompanying drawings, which illustrate one form of our invention, Figure 1 is a horizontal section of a form of furnace on line I I of Fig. 2. Fig. 2 is a vertical section on line II II of Fig. 1, and Fig. 3 is a partial vertical section of a modified form.

Referring particularly to Figs. 1, 2, 1 is the fire-brick base of the furnace, preferably provided with spaces or apertures lilled with asbestos or other suitable heat-insulator 2. 3 4 are inner and outer spaced walls, the intermediate space being likewise filled with asbestos 5. The inner wall 3 is of fire-brick and is intcriorly lined, as is also the base 1, with a highly-refractory facing 6, the character of which will depend upon the nature of the charge or material to be treated. The cover 7 is also of refractory material constructed of several sections and preferably overlaid by a heat-insulating body 8. The furnace-chamber is divided into any desired number of independent compartments 9 10, separated by refractory walls. As shown, these dividing-walls comprise resistors 11, which maybe of carbon or a carbonaceous mixture, and refractory facings 12 12, which may be of the same character as the lining 6. The

several resistors 11 are connected electrically in series by resistors or connectors 13, placed at opposite ends of adjacent compartments and protected by the refractory facings 12. The principal terminals are shown at 14 14, and the source of current is c'liagrammatieally indicated at 16 is an auxiliary terminal, of which any desired number may be employed. The auxiliary terminal or terminals are electrically connected at one or more intermediate points with the resistors 11 and are connected with the generator 15 through a switch 17, by the manipulation of which the current may be caused to traverse a part only of the resistors, whereby a corresponding section of the furnace is heated. In the construction illustrated the end compartments 1O 10 are heated from one side wall only, whereas the intermediate compartments are heated from both side walls. In this case the end compartments are preferably of proportionatelyreduced size in order that the temperature may be uniform throughout the furnace.

The furnace above described is designed to be charged and emptied by removing the required number of plates of the cover 7. e

may modify the furnace, however, to permit the several compartments to be filled and. emptied from the side, the openings being alternately at one or the other side, as indicated by dotted lines at 18 18 in Fig. 1, or we may provide means for lowering the baseplate of one or several compartments by hydraulic or other means, as shown at 19 in Fig. 3, in which case the charging and, discharging is accomplished through the bottom of the furnace.

If desired, the electrical connection between the several resistors in the side walls may be made alternately above and below the compartments instead of at the ends, as shown. The compartments will be of such form and size as will best conform to the material to be treated.

e claim- 1. An electric furnace comprising a plurality of independent consecutively-disposed compartments, and resistors arranged to heat said compartments and electrically connected in series, substantially as described.

2. An electric furnace comprising a plurality of independent consecutively-disposed compartments separated by refractory walls,

and resistors arranged within said walls and electrically connected in series, substantially as described.

'3. An electric furnace comprising a plurality of independent compartments, resistors said Walls and electrically connected in series, and auxiliary terminals in electrical connection with said resistors, substantially as described.

6. An electric furnace comprising an apertured base, heat-insulating material in the apertures of said base, a plurality of independent compartments on said base, and resistors arranged to heat said compartments and electrically connected in series, substantially as described.

In testimony whereof we affix our signatures in presence of two witnesses.

FRANCIS A. J. FITZ GERALD. PETER MON. BENNIE.

Witnesses:

WILLIAM F. FLAHERTY, WILLIAM J. MAXWELL. 

